Java Scope

Java Scope

In Java, variables are confined to the region where they are declared, known as their scope.

Method Scope

Variables declared within a method are accessible throughout the method’s entirety beyond the line of code where they’re declared.

Example

public class Main {
  public static void main(String[] args) {

    // Code here CANNOT use x

    int x = 100;

    // Code here can use x
    System.out.println(x);
  }
}

Block Scope

A code block encompasses all the code enclosed within curly braces { }.

Variables declared within code blocks are only accessible within the block of code enclosed by curly braces, following the line where the variable was declared.

Example

public class Main {
  public static void main(String[] args) {

    // Code here CANNOT use x

    { // This is a block

      // Code here CANNOT use x

      int x = 100;

      // Code here CAN use x
      System.out.println(x);

    } // The block ends here

  // Code here CANNOT use x

  }
}